This invention relates to measuring instruments, and more particularly, to measuring gages adaptable to measure a dimension of a body, and still more particularly, to a precision caliper gage adaptable to measure interior or exterior dimensions of a body.
Precision caliper gages have been known and widely used for a long time in many countries and for many industrial applications.
However, as I have cited below, previous measuring calipers were designed to perform a single type of measurement, as, for example, a measurement of the wall of a tube. Or, in some cases, the instrument may include two sets of interchangeable arms so that the device may measure an interior or an exterior dimension of a cylinder. As I have found through long experience, and as is readily seen in the following references, the capabilities of the measuring calipers previously designed are extremely limited.
Some of the typical measuring calipers which I have found in the prior art are described in the following U.S. Pat. Nos.:
______________________________________ 1,060,111 Muncaster April 29, 1913 1,967,618 Jazwieck July 24, 1934 1,990,138 Schuster February 5, 1935 2,083,373 Hardesty et al June 8, 1937 2,553,574 Gray May 22, 1951 2,634,505 Petch April 14, 1953 2,785,471 Aldeborgh et al March 19, 1957 2,791,033 Walters May 7, 1957 ______________________________________